After continental drift smashes open their cave and leaves them wandering over landscapes such as the floor of a now-empty ocean, the Crood family encounters every protective parent’s worst nightmare – a guy (named Guy, voiced by Ryan Reynolds) who wins their daughter’s heart by showing her how to start fires.

Dads today are still terrified of that scenario.

The inspiration for The Croods was to tell the story of how a family survives in tough times. In this case, they don’t have to worry about paying bills – they’re more worried about being eaten. Their prehistoric period is filled with assorted colorful and deadly hybrids such as piranhakeets (picture pink flocks of piranhas with parakeet wings) and rainbow-hued sabertooth tigers.

After they lose their cave, the Croods have to go in search of a new subterranean dwelling, which leads them into the forbidden outside world. “This is the world’s first family road trip,” says Kirk DeMicco (2008’s Space Chimps), who co-directed with Chris Sanders (How to Train Your Dragon, Lilo & Stitch.)

“Our cavemen are very gifted,” Sanders adds. “They can run 40 miles an hour, can throw a rock many many miles. Physically they’re very capable, but mentally we have a lot of beginner minds. “

“They’re not dumb, but they’re like kids,” DeMicco adds. “They have literal minds that have blindspots. When they see fire for first time, they think it’s alive.”

From right to left, here are the characters in the family portrait (click the image for a larger version):

Grug (voiced by Nicolas Cage): The filmmakers call him the animated caveman version of well-meaning but hopelessly outdated cinematic dads such as Steve Martin in Father of the Bride or Spencer Tracy in Guess Who’s Coming to Dinner. “Everyone deals with change in their family, and who deals with change more than a father with kids growing up?” says DeMicco. “Nic Cage has done a great job of making him likeable, while at the same time overprotective, which is not an easy thing to do.”

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Eep (voiced by Emma Stone): “Of all The Croods, she was the one who liked the cave they lived in the least,” Sanders says. “The Croods spent much of their time in the dark, and that was Grug’s way of keeping his family safe. When their cave falls down and they’re forced to go on this journey, everyone is a little freaked out – but not Eep.” She’s eager to do some traveling. “For The Croods, anything new is super scary. New is bad. On this journey, every single thing they come across is going to be new. For Grug, it’s a nightmare. For Eep, it’s the greatest thing that ever happened to her.”

Ugga (voiced by Catherine Keener): “She’s probably more open-minded than Grug when it comes to change, but she’s very much his partner in this thing,” Sanders says. “For a mom, she has the world’s hardest job. Keeping this family alive is not easy. Just getting lunch is a life and death situation. This is the universal thing – dads, moms all want to keep their family safe. ‘How much freedom do I let them have? … I wish I could keep them in sight all the time, because then everything will be okay.”

Sandy the baby: Sanders calls her “half Tasmanian devil and half child.” She doesn’t speak; growling is more her thing and Oscar-winning sound designer Randy Thom is building her voice from compiled creature noises. “She’s still ferocious, still bites, and it’s kind of the way that Grug wants his kids to be. She’s a survivor. She might be the one to make it better than any of them.”

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Gran (voiced by Cloris Leachman): “She’s like this ferocious, almost crocodile-type woman,” DeMicco said. “We always say: ‘She’s older than dirt – some say she’s 45. She has lived a very long life in a short amount of time.” She is the main antagonist for Grug, Nicolas Cage’s pater familias.

Thunk (voiced by Clark Duke, Hot Tub Time Machine): This middle-sibling is described by DeMicco as “6-foot-9, 320 pounds, and 9 years old. He’s so big and so wants to be like his sister and his dad. He has the best heart and the worst coordination.” Though everyone in the family is evolving, Thunk may already be at the zenith of his intellect. (Think of him as the caveman Fredo.) “I don’t think Thunk will ever catch up,” Sanders says. “We love him.”

Finally, there’s Guy (voiced by Ryan Reynolds, and pictured with his sloth-like pet at left and right above): “Guy is human being 2.0; he’s not as a strong as the Croods but he’s more about using his brain,” Sanders says. “When they discover he can make fire, they kidnap him, stick him in a hollow log, and keep him.” “Like a human lighter,” DeMicco adds.

Of course, Eep eventually falls for him, and vice versa.“This is really Grug’s nightmare,” Sanders says. “Guy is full of ideas. Croods don’t really have ideas.” He introduces the Croods to shoes, for example, and suggests that life doesn’t have to be lived in a dark cave. Such ideas make Eep swoon even more.